I remember seeing a few box and whisker plots in grad school but I do not encounter them very often now. I have used and see histograms more often. I personally think histograms are easier to understand for most people but I would consider the target audience when picking out one of these graphs. I might choose a box and whisker plot if I was presenting to a group of statisticians because they might want to see the interquartile range and would be familiar with this type of graph. For most other audiences I would probably stick with a histogram because it is a simple graph and is easier to understand.